Pre-assembled bellows-type arrangement for covering articulated shafts

ABSTRACT

The invention relates to an arrangement for covering a shaft-type mechanism and/or a joint-type connection of two shafts or a steering gear, comprising a bellows-type element ( 10 ). Said bellows-type element ( 10 ) has a collar-type essentially ring-shaped section ( 14 ) at each end, with an open clamping, pressing or shrink ring ( 20 ) or a so-called open hose clamp located thereon. Said hose clamp is pre-stressed in the direction of the centre in such a way that the two open ends ( 22, 24 ) mutually overlap each other and the ring or the clamp is automatically held tight on the respective section.

BACKGROUND OF THE INVENTION

The present invention relates to an arrangement provided for sheathing ashaft-like element, and/or a connection between two shafts—or ajoint—and a method for arranging a bellows-like sheathing of a driveshaft.

Bellows-like arrangements are known for sheathing shaft-like elements,connections of shafts, such as in particular join connections or driveshafts, gear shafts and the like. Especially in the auto industry, driveshafts, gear joints, etc. are sheathed by means of rubber bellowsjoints, e.g. in order to protect the joints and prevent leakage of thelubrication.

As a rule, rubber bellows joints are mounted on the drive shafts with,already mounted at each end of the bellows, closed hose clamps orclamping rings or press rings such as the commercially very well known“Oetiker” clamps that are clamped or contracted on by means of suitabletools or devices for solid, tight connection of the bellows with therespective shaft sections.

With this pre-mounted, already closed arrangement of the clamps orclamping or press rings, on the one hand cost-intensive measures arenecessary on the bellows so that the non-contracted or unclamped, loosemounted clamps or rings are held on collar-like end sections, and inaddition, after loose mounting of the bellows on the drive shaft to besheathed, any defective clamps or rings can no longer be replaced and/oradditional clamps or rings or replacement clamps or ring cannot bemounted.

A still open clamping ring already pre-mounted on a rubber bellows endis indeed proposed in EP 0 545 629 that is held “automatically” on amounting section at each end of the rubber bellows. After mounting therubber ring, however, this clamping ring must first be clamped andclosed in a first mounting step by applying a tool, to then becompressed in a second mounting step if necessary. The latter is trueespecially when, due to manufacturing tolerances, the clamping or pressring does not already allow secure mounting of the bellows by clamping.

SUMMARY OF THE INVENTION

It is therefore the technical problem of the present invention topropose a measure such that already loosely pre-mounted clamps orclamping or press rings can also be easily held on a bellows and can beeasily replaced, or additional clamps or rings can be mounted thatsubsequently allow a secure, solid mounting of the bellows preferablyonly by means of one further processing step.

It is proposed that an arrangement intended for sheathing a shaft-likeelement and/or a connection between two shafts or a drive shaft andhaving a bellow-like element which in turn has at each end a collar-likesection designed largely annularly, with, mounted on it, an openclamping, press or contracting ring or a so-called open hose clamp thatis pre-stressed toward the center such that the two ends of the ring orclamping belt mutually overlap and the ring or the clamp isautomatically retained on the section. In the two belt ends of the clampor ring, meshing or interlocking sections are provided in order, whenthe ring or the clamp widens, to mesh or interlock and snap the ringbelt or clamp belt closed.

Also proposed is a method for arranging a bellows-like sheathing of adrive shaft or a gear joint, for example to protect the lubrication of ashaft connection or a joint, in connection with which at each end thebellows-like sheathing is provided at a collar-like end section with anopen clamping, press or contracting ring or a hose clamp that ispre-stressed toward the center and the ends of which are provided withcorresponding contours to form a meshing or interlocking connection ofthe ends, and these ends mutually overlap due to the pre-stressing suchthat subsequently at least the one collar section at each end is slid insleeve-like manner or pushed on a largely circular support[ sectionprovided an a shaft or in the area of the shaft end. This supportsection is provided for mounting and holding one of the ends of thebellows-like sheathing, in connection with which, when the collar-likeend of the bellows-like sheathing is slid in sleeve-like manner orpushed on and widened, the clamping, press or contracting ring or thehose clamp is widened such that the two ends of the ring or the clampare moved far enough in the belt-widening direction that the meshing orinterlocking solid connection of the two belt ends arises due to thecontours provided for, and then, by means of a press, contracting orclamping step, the ring or the clamp is fastened on the collar-like endin the diameter-reducing direction to produce the solid connectionbetween the bellows-like element and the shaft.

The arrangement and, respectively, the method defined according to theinvention is of course suitable for sheathing shafts or shaft-likeelements of different kinds, for sheathing or protecting joint-likeconnections, drive shafts, gear shafts, etc. The widest variety ofbellows-like elements made of the widest variety of elastic materialssuch as rubber, elastomer, thermoplastic plastics, etc. can also be usedfor the arrangements and/or methods according to the invention, as canthe widest variety of hose clamps, clamping or press rings as well. Inthis connection; the ends joining the two belt ends of the clamps or therings can have the widest variety of designs. The essential point isthat the two ends have a contour which, when the clamp or the belt iswidened, allows a meshing or interlocking connection or allows them toslide into each other or snap in. In this connection, the followingclamps should be pointed out, for example: those described in EP 570742, EP 591648, EP 503 609, CH 561383, CH 555 026, CH 669 642, CH 677010, CH 679 945, EP 543 338, as well as so-called “Oetiker” clamps, asare widely used commercially and very well known, just to name a few.

The major advantage of the method proposed according to the invention isin the fact that the pre-stressed clamping, press or contracting ringselected according to the invention can be designed smaller and moreaccurate and is thereby less expensive to manufacture. In addition,there is a smaller contracting path than there is, for example, with analready mounted, closed ring.

Another advantage results from the fact that the ring according to theinvention can be inserted from the side and can be precisely positionedwhere it is to be mounted in the end. In this way, a contracting orpress ring can also be mounted at a specific location that is providedwith corresponding production or mounting data, which should be placedprecisely at that location. These—if necessary—important details on thecontracting or press ring placed according to the invention can thus bereviewed later; for example, they can be stamped into the press ring.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in more detail below with reference to theattached figures. They show:

FIG. 1 in exploded view and as seen in the direction of an opening, abellows having at one end an open contracting or press ring as proposedby the invention,

FIG. 2 a cutout from FIG. 1, showing the overlapping belt ends of thecontracting or press ring from FIG. 1,

FIG. 3 possible designs of contracting or press rings, and FIG. 4 knownfrom the state of the art for the pre-mounted arrangement of the pressand contracting rings,

FIG. 5 the contracting or press ring from FIG. 1 in the non-mountedstatus,

FIG. 6 the bellows from FIG. 1 in the status mounted on a shaft endbefore compression of the press or contracting ring,

FIG. 6a a rear-axle shaft, and respectively, a drive shaft by means of abellows, corresponding to that of FIG. 6,

FIG. 7 a possible design of the two belt ends of the press orcontracting ring,

FIG. 8 a further form of construction of the connection of the press orcontracting ring, and

FIG. 9 as an example, an installation for contracting or clamping theclamping ring or press ring on the bellows.

DETAILED DESCRIPTION

FIG. 1 shows in an exploded view as seen in the direction of the largerbellows end, an arrangement according to the invention having a bellows10 with the individual bellows sections 12. The bellows 10 may be madeof a rubber or a rubber mixture, for example, or of another suitableelastic material, such as a suitable thermoplastic plastic. On thelarger collar-like end 14 visible in FIG. 1, a clamping or press orcontracting ring 20 is mounted. The two ends 22 and 24 are mountedloosely and mutually overlapping, i.e., in other words, the contractingring 20 is loose and can be removed at any time by pulling apart the twoends of the collar 14 of the bellows 10. In order for the contractingring 20 to be firmly retained automatically on the collar 14 at each endof the bellows 10, as already mentioned it is designed pre-stressedtoward the middle of the ring on the one hand, and in addition, thecollar 14 preferably has a further, second edge like grading 18 designedtoward the first bellows section. The edge 16 of the collar 14 as wellas the grading 18 are preferably designed at such a distance from eachother that the ring can be attached with its width between them. Theedge 16 comprises a retaining section, such as a groove-like section,that holds the ring 20 on the collar 14 when the ring 20 is in an open,non-mounted status. In particular in FIG. 2, in which the two belt ends22 and 24 from FIG. 1 are illustrated enlarged, it can be clearly seenthat the one belt end 22 has a protruding tongue 23 or latch withsections protruding laterally, i.e., crosswise to the direction of thebelt. A corresponding recess or notching 25—not shown—is provided in theother belt end 24 so that when the ring belt 20 is opened up, the latch23 can snap into the corresponding recess 25 without loss. As canfurthermore be seen in FIG. 2, that belt end is arranged directedoutward that has the latch or the tongue 23.

It was already attempted in the state of the art to solve at least aportion of the technical problem at the basis of this invention; i.e.,to hold a not yet contracted press or clamping or contracting ring onthe collar-like end of a bellows. A possible start of a solution isshown in FIG. 3, in that, for example, the belt is designed oval orelliptic in order to achieve a clamping effect vis-a-vis the collarsurface. According to a further illustration from FIG. 3, the belt isarranged triangularly in order to achieve a clamping effect vis-a-visthe collar at least at three support sections.

In FIG. 4, on the other hand, a further starting point for a solution isshown, in that it is also conceivable that during the pre-mounting ofthe already closed clamping or contracting ring, the bellows is reducedin diameter by an inward-facing deformation thereof, so that the alreadyclosed ring can be pulled on. This method is indeed possible inconnection with rubber-like materials for bellows but hardly inconnection with the thermoplastic materials or elastomers such asHytrel, Anitel, etc. often used nowadays.

In addition, the potential solutions illustrated in FIG. 3 and 4 alwaysstart from already closed clamping or contracting rings, occasionally adisadvantage.

For this reason, it is proposed to use the contracting or press ring 20shown in FIG. 5, which is designed pre-stressed toward the center, andto have the two belt ends 22 and 24 overlap in loose status. Thiscreates a tensioning or clamping effect which automatically holds thepress or contracting ring 20 on the collar-like end 14, as shown in FIG.1.

When mounting the bellows 10 with pre-mounted contracting or press ring20, such as a so-called multi-crimp ring (MCR) on the metal counterpieceor end of a shaft, the collarlike end 14 of the bellows is widened. TheMCR overlapping with the two open belt ends in delivery condition islikewise extended due to this widening process, and the two endsautomatically snap in on the same belt level, as FIG. 6 clearly shows.The latch or tongue 23 snaps into the corresponding recess 25 in thebelt end 24, and due to the design of the tongue or latch 23 with thesections protruding laterally crosswise to the belt direction, the twoends are locked.

FIG. 6a shows a rear-axle shaft 50 having two joints arranged on the onehand between a drive shaft 51 and connecting shaft or steering shaft 53,and on the other hand between the connecting or steering shaft 53 andthe wheel shaft or wheel-hub 55. The two joints are each sheathed bymeans of a bellows 10 that protects each of the joints and “secures”their lubrication. The two bellows 10 are in turn secured withcontracting or press rings 20 proposed according to the invention, withthe two belt ends 22 and 24 as well as the tongue 23 engaging acorresponding recess are clearly recognizable on the contracting ringnear the drive shaft 51. The major advantage of the present inventionagain becomes clear with the help of such a rear-axle shaft or driveshaft 50, in that it can be-delivered with “loose” contracting or pressrings, but with no risk that these press or contracting rings may falloff. There is also the possibility at any time to remove one of thealready mounted contracting or press rings even if the rear-axle shafthas already been definitively mounted, since a new, still opencontracting or press ring can still be pushed laterally onto the collarto be compressed.

Possible forms of construction of belt ends are illustrated in FIGS. 7and 8, for example, in connection with which in FIG. 7, the latchprotruding from the one end 22 or the edge 26 has the aforementionedsections 28 protruding crosswise to the belt direction. Furthermore, theend of the belt section 22 has sections 29 protruding laterally relativeto the latch 23, in order to prevent a lateral breaking out of the endareas 26 grasped from behind by the two sections 28. The latch and thecorresponding recess are preferably designed such that a meshing isensured without loss.

FIG. 8 shows a further form of construction of a connection, inconnection with which the latch or tongue 23′ arranged once again in themiddle of the belt end 22 is mounted meshing in a corresponding recess25′. In this form of construction, several sections protruding laterallyand crosswise to the belt direction are provided that additionally havespecial contours.

The two belt connections or belt closures shown in FIGS. 7 and 8 are ofcourse only examples and are only used to better comprehend the presentinvention. Of course, this also covers any number of other belt locks orconnections that make possible an automatic meshing or interlockingconnection or snapping in of the ends during the widening step of the b.

After successfully mounting the bellows on a shaft end, as shown inFIGS. 6 and 6a, only the press or contracting ring or the pre-mountedMCR then need to be clamped or compressed. Once again as an example,FIG. 9 shows such an installation that is suitable for contractingpre-mounted MCRs. In this procedure, the lock of the contracting orpress ring, attached in the pre-mounted status, is sealed such that itcan no longer be automatically opened or separated. The installation 40shown in FIG. 9 has, described in simplified manner, clamping segments41 able to be actuated annularly inward and together displaying anannular opening 43 with their inner contours. With a hydraulic orpneumatic installation 42, the individual clamping segments 41 can bepressed or driven radially inward in order to reduce the diameter of orcontract the contracting or press ring.

The present new development thus includes clamping or contracting ringsor so-called multi-crimp rings (MCR) with open ends and known mechanicallock. Due to the fact that these MCRs are produced with open ends, theycan be manufactured with corresponding pre-stress. This pre-stresscauses a spring effect in the direction of the ring center. This springeffect can be used to the effect that the ring automatically holds, willno structural adaptation on the bellows, in the area of the end collarin an appropriately provided groove, e.g. provided for receiving MCRs.This is because, as is well known, practically every model of bellows ismanufactured with the aforementioned groove. This groove can be designedrunning throughout or also as just an individual cam arranged on thebellows periphery. A pre-mounting is thus possible, namely without anystructural modification on the bellows, i.e., every mass-productionbellows can be equipped with the integrated MCR, provided as a system,thereby saving a work step during definitive mounting.

The forms of construction or installations shown in FIGS. 1-9 inconnection with the arrangement of bellows are of course only examplesintended to explain in greater detail the inventive step or theaforementioned mounting step. The design of the bellows, particularlythe material used for the bellows, and also the design of thecontracting or press ring or the so-called MCR, and in turn the materialused for this, may be modified in any desired manner, of course, and theinvention is not limited to any form of construction. It has indeed beenshown that for manufacturing the MCR, aluminum is suitable, for examplebut stainless steel or any other suitable metallic materials can also beused for this, of course.

What is claimed is:
 1. Arrangement provided for sheathing a shaftelement and/or a connection between two shafts and/or steering gears,having: a bellows element (10) a collar section (14) at each end of thebellows element designed largely annularly an open clamping, press orcontracting ring (20) or an open hose clamp arranged on each collarsection, the ring or clamp being pre-stressed toward a center of thering or clamp such that two ends (22, 24) of the ring or clamp mutuallyoverlap and the ring or the clamp is automatically retained on thecollar section, and that in the two ends of the clamp or the ring,meshing or interlocking sections (23, 25) are provided so that when thering or clamp is widened, the meshing or interlocking sections mesh orinterlock and snap the ring or clamp closed.
 2. Arrangement according toclaim 1, characterized in that at least one retaining section (16) isprovided on the collar section (14) in order to hold the ring or clampin open, non-mounted status on the collar section.
 3. Arrangementaccording to one of the claims 1 or 2, characterized in that one of thetwo ends of the ring or the clamp has at least one tongue or latch (23)protruding in the direction of the ring or the clamp and with sectionsprotruding crosswise to the latch or tongue, and the other of the twoends of the ring or clamp has at least one notching or punch out (25)corresponding at least nearly to the contour of the latch or tongue, inorder to receive and close them without loss during mounting of thebellows and widening of the ring or the clamp of the ring or clamp. 4.Arrangement according to claim 3, characterized in that when the clampis open and loosely pre-mounted or when the ring is open, the one(22) ofthe two ends that has the tongue or latch rests facing outward on theother (24) of the two ends having the notching or punch out. 5.Arrangement according to one of the claims 1 or 2, characterized in thatthe clamping or contracting ring is a multi-crimp ring.
 6. Arrangementaccording to claim 2, characterized in that the retaining section is anedge at each end, or a groove section is designed on each end of thecollar in order to hold the clamp or ring in a pre-mounted status. 7.Method for arranging a bellows sheathing of a drive shaft or a gearjoint, comprising steps of: providing an open clamping, press orcontracting ring or a hose clamp at each end of the bellows sheathing ata collar end section, two ends of the open ring or clamp havingcorresponding contours to form a meshing or interlocking connection ofthe two ends, and the two ends mutually overlapping, pushing on orsliding at least the one collar end section in sleeve manner onto alargely circular support surface provided at the shaft end and providedfor the mounting and holding one of the ends of the bellows sheathing,and when the bellows sheathing is pushed on or slid on in sleeve mannerand the collar end of the bellows sheathing is widened, the clamping,press or contracting ring or the clamp is widened such that the two endsof the ring or clamp are moved in a widening direction far enough thatthe firm meshing or interlocking connection between the two ends iscreated, and attaching the ring or the clamp on the collar end by apressing or contracting process in the diameter-reducing direction toproduce a solid connection between the bellow and the shaft or shaftend.
 8. Method according to claim 7, characterized in that the pressring or clamping ring or contracting ring or the hose clamp ispre-stressed toward a center of the ring or clamp such that the two endsof the ring or clamp mutually overlap in a loose pre-mounted status.